<?php
function msubstr($str, $start=0, $length, $charset="utf-8", $suffix=true){
    if(function_exists("mb_substr")){
        return mb_substr($str, $start, $length, $charset);
    }else if(function_exists('iconv_substr')) {
        return iconv_substr($str,$start,$length,$charset);
    }
    $re['utf-8']   = "/[\x01-\x7f]|[\xc2-\xdf][\x80-\xbf]|[\xe0-\xef][\x80-\xbf]{2}|[\xf0-\xff][\x80-\xbf]{3}/";
    $re['gb2312'] = "/[\x01-\x7f]|[\xb0-\xf7][\xa0-\xfe]/";
    $re['gbk']    = "/[\x01-\x7f]|[\x81-\xfe][\x40-\xfe]/";
    $re['big5']   = "/[\x01-\x7f]|[\x81-\xfe]([\x40-\x7e]|\xa1-\xfe])/";
    preg_match_all($re[$charset], $str, $match);
    $slice = join("",array_slice($match[0], $start, $length));
    if($suffix) return $slice."...";
    return $slice;
}

//$url 地址 
//$str 是否 提示信息 
//$s 1不要中断执行
function go($url,$str='',$s=0){
	$alert = $str=='' ? '' : 'alert("'.$str.'");';
	
	if($s==0){
		die('<script>'.$alert.'location.replace("'.$url.'");</script>');
	}
	
	if($s==1){
		echo '<script>'.$alert.'window.top.location.replace("'.$url.'");</script>';
	}
	
}


//字符型过滤
function str_set($str){
	$str = strip_tags($str);
	$str = str_replace(' ','',$str);
	$str = str_replace('　','',$str);
	$str = str_replace('&nbsp;','',$str);
	$str = str_replace('<','',$str);
	$str = str_replace('>','',$str);
	$str = stripcslashes($str);
	
	return $str;
}

?>